Duplicating device for lathes



P 1965 N1). SCHOENROCK 3, 04,671

PLI I V NG D a h 1962 heats-Sheet 1 ICE FOR LATHES 1 N VEN TOR. IVoRBERTQJcHaEN/wcK if/ WW ATToRIvE Y6 P 1965 N. o. SCHOENROCK 3,204,671

DUPLICATING DEVICE FOR LATHES Original Filed March 15, 1962 2 Sheets-Sheet 2 g mmmzatmmmstemAL I l v v v y y I IN VENTOR lVakas/ard Janos/work BY am ATTORNEYJ United States Patent 3,204,671 DUPLICA'IING DEVICE FOR LATHES Norbert 0. Schoenroclr, 21'5 Kreig St., Mankato, Minn. Continuation of application Ser. No. 180,416, Mar. 15, 1962. This application July 22,1963, Ser. No. 296,691 4 Claims. (Cl. 142-7) This application is a continuation of application Serial No. 180,416, filed March 15, 1962, now abandoned.

The present invention relates to the machine tool art and more particularly to a device to be used with a lathe for enabling a pattern to be duplicated.

A number of devices have been previously proposed for enabling a lathe operator to duplicate a pattern of a selected design. These devices have, however, suffered from certain shortcomings and have been to some extent ineffective in operation.

One of the previous duplicator devices of the type described included a means for supporting a pattern on the opposite side of the lathe from which the operator normally stands while the work is being performed. In this type of device, however, a substantial inconvenience is associated with removing and replacing the pattern. Morever, it may be difiiicult at times for the operator to see the pattern so as to readily anticipate the required movements which must be made in following the pattern. As a result, operation of this prior device was associated with a certain amount of inconvenience and wasted effort.

Another device of the type described which has been previously proposed includes a pattern mounting device positioned on the same side of the lathe which the operator stands but the pattern projects a substantial distance laterally from the lathe into the operators station and in effect occupies the position which the operator would normally take while working at the lathe. This is a significant disadvantage since the best results are obtained by stationing the operator close to the work where he can easily and adequately inspect the progress of the cutting operation.

In other prior devices of the type described, the cutting head has been inherently difilcult to move and accurately position since the support means therefor will tend to bind or introduce excessive friction.

In still other devices of the type described, the movable support for the tool head has been complicated in construction and as a result expensive to manufacture.

In view of these and other defects in the prior art it is thus one object of the present invention to provide an improved duplicating device of the type described in which the movable mounting means for the tool is characterized by a relatively small amount of friction and will have no tendency to bind.

It is another object of the present invention to provide an improved duplicator for a lathe including selfaligning bearing means adapted to support a cutting head for movement on mutually perpendicular axes.

A further object of the present invention is the provision of an improved duplicator of the type described including a means for supporting a pattern on the same side of the lathe as the operator station which will not interfere with the operators ability to position himself relatively close to the lathe so that the cutting operation can be closely observed.

A further object of the present invention is the provision of an improved duplicating device of the type described including a cutting head mounted for simultaneous, lateral and longitudinal movement with respect to the lathe bed and a pattern supporting means mounted on the same side of the lathe bed and below the cutting head.

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Another object of the present invention is the provision of an improved duplicating device of the type described including a quick acting grip means for supporting the pattern.

Yet another object of the present invention is the provision of an improved duplicator for lathes including four separate and identical bearing blocks which can be manufactured at low cost and will reliably maintain the tool cutting head in the desired position and enable it to move along mutually perpendicular axes with a min imum of friction.

Other objects of the invention will become apparent as the description proceeds.

To the accomplishment of the foregoing and related ends, this invention then comprises the features hereinafter fully described and particularly pointed out in the claims, the following description setting forth in detail certain illustrative embodiments of the invention, these being indicative, however, of but a few of the various ways in which the principles of the invention may be employed.

FIGURE 1 is a perspective view of a lathe fitted with a duplicator according to the preferred form of the present invention;

FIGURE 2 is a vertical sectional view taken on line 2-2 of FIGURE 1;

FIGURE 3 is a vertical sectional view taken on line 3--3 of FIGURE 1;

FIGURE 4 is a partial plan view taken. on line 44 of FIGURE 2; and

FIGURE 5 is a vertical sectional view taken on line 55 of FIGURE 4.

Referring now to the drawings there is shown in FIGURE 1, a lathe of any suitable type. By way of example in the form of the invention illustrated, the lathe 10 comprises a wood lathe of the type used for manual training in high schools.

The lathe 10 includes a hollow casing 12 having the usual drive means therein and a turning means such as a holder or chuck 14 adapted to support and impart rotary movement to a workpiece such as a piece of wood stock 16. The lathe also includes a lathe bed indicated generally at 18 including a pair of flat parallel and horizontally disposed guideways 20 and 22 separated by an opening 24 which extends longitudinally of the lathe bed. At the opposite end of the lathe bed from the easing 12 is provided a longitudinally adjustable support means 26 of conventional construction including a holder 28' mounted for rotation therein and adapted to engage the opposite end of the wood stock 16 from that supported by the chuck 14. The lathe 10 can also be provided with a plurality of support legs (not shown) for spacing the bed 18 the desired distance from the floor. While one form'of lathe adapted for use with the invention has been described briefly, it will be understood that the invention canbe employed with various other types of lathes, if desired.

Suitably rigidly aflixed to the lathe bed 18 are a pair of identical brocket members 30 and 32 which, in the form of the invention shown, comprise castings having horizontally disposed legs 34 and 36 respectively, a pair of upwardly extending support portions 34:: and 36a respectively and downwardly extending portions 34b and 36b respectively.

Rigidly secured in a horizontally disposed position between the support portions 34a and 36a are a pair of parallel and horizontally disposed slide means such as rods 38 and 40. The rods 28 and 40 are rigidly secured to the upward ends of the support members 34a and 36a by passing them through bored openings within which they are held by means of suitable fasteners such as set screws 42.

The brackets 30 and 32 are aflixed to the lathe bed 18 with fasteners of suitable type which as best seen in FIG- URE 3, preferably comprise identical vertically disposed bolts 50, only one of which is shown. The bolts 50 each extend through a suitable bore 52 in the horizontal portions 34 and 36 of brackets 30 and 32 and project downwardly through a clamping plate 54 disposed horizontally within the opening 24 between the guideways 2t) and 22.

Threadedly affixed to the upward end of each bolt 50 is a suitable fastener such as a thumb nut 56 which will enable an operator to turn the clamping plate 54 until it is engaged tightly against the lower surfaces of each of the guideways and 22. With the type of fastener employed, the brackets and 32 can be quickly and easily placed in position on the lathe 18 or removed from the lathe when desired. Moreover, by loosening each of the thumb nuts 56, the brackets 30 and 32 can be moved either toward or away from one another to change the spacing therebetween so as to best support slide rods and pattern. After the brackets 30 and 32 have been fastened in the desired position on the lathe bed 18, the set screws 42 should be tightened so as to lock the rods 38 and 40 in the desired position.

Slidably mounted upon the rods 38 and 40 is a movable cutting head mounting assembly including two pairs of longitudinally and laterally spaced identical bearing blocks designated through 53. As best seen in FIGURE 5, each bearing block, the bearing block 50 being typical, includes a pair of bores 54 and 55 which are spaced vertically and positioned at right angles to one another, the bore 54 being positioned above the bore 55 and extending at right angles thereto longitudinally of the apparatus while the bore 55 extends laterally thereof, in a horizontal plane.

Mounted within each of bores 54 and 55 is a suitable bearing means such as identical ball bushings 56 constructed in any well known and conventional manner and may include a carriage portion 58 having circumferentially spaced ball channels 60 therein each including a plurality of balls 62. At each end are provided seals 64 and 66. Adjacent the outward edge of the seals 64 and 66 are provided felt packing rings 68, the latter being secured in position by suitable fastening rings 70 which include portions adapted to engage the bores 54 and 55 to retain the felt packing members and ball bushings in position. Extending through the transverse bores of the blocks 50 through 53 is a slide means composed of a pair of horizontally disposed and transversely extending slide rods 72 and 74. Adjacent ends of rods 72 and 74 are rigidly secured together by connecting means such as a transversely disposed bar 76 including openings positioned over the ends of the rods 72 and 74. Set screws 78 or other fasteners secure the bar 76 in place. The other ends of rods 72 and 74 are secured to the lower end of a tool support head 80 including a tool bit 82 of generally wellknown construction at the upward end thereof.

The tool bit 82 includes a slide means 84 which is secured in the selected position by a fastener 86. Slide means 84 is mounted for rotary adjustment about a vertical axis through the provision of a bearing 88. At the inward end of the tool holder is secured a tool of a suitable construction.

Rigidly secured to the outward end of the tool holder 80 is a grasping means such as a pair of downwardly inclined and diverging handle members 92 and 94 adapted to be gripped by an operator to position the tool holder 80. As best seen in FIGURES 1 and 2, the tool holder 80 is itself positioned generally vertically with the tool bit 82 located substantially vertically of the point at which the handles 92 and 94 are afiixed thereto.

Between and slightly below the handles 92 and 94 is provided a bracket 96 including a vertical bore 98 within which is mounted for vertical and rotational adjustment a vertically disposed and elongated follower 100. The follower 100 is secured in a selected position within the bore 98 by means of a fastener 102 which is threaded within the bracket 96. As can be best seen in FIGURES 1 and 2, the lower end of the follower 100 isrounded throughout most of its length and provided with a relatively sharp vertically disposed knife edge portion 106. When the pattern, to be described hereinbelow, is relatively smooth in contour, the rounded portion of the follower 100 can be placed in engagement with the side of the pattern and will accurately and reliably position the tool support at 80 so as to duplicate the pattern. When the pattern is relatively intricate in design, the follower 100 should be loosened within the bracket 96 and turned so that the relatively sharp knife edge portion 106 engages the pattern. By this means the pattern can be accurately followed by the tool support head 80 even though the pattern includes numerous sharp angles.

Positioned on the downwardly extending portion 34b of the bracket 30 is a gripping means comprising a pair of gripping members 110 and 112, clearly shown in FIG- URE 1. Positioned substantially opposite therefrom on the downwardly extending portion 36b of the bracket 32 is a fastener comprising a crank 114 which is threaded within a horizontal opening extending through the portion 36b in substantial alignment with the gripping members 110 and 112. Between the gripping members 110 and 112 and the crank 114 is positioned a pattern 116 of any suitable type which while illustrated as a piece turned on a lathe it may, if desired, comprise a planar pattern having either a straight or irregular edge. When the pattern 116 is to be changed, the crank 114 need only be rotated a few turns and a new pattern placed in position. The crank 114 can then be tightened again to lock the new pattern in position below the tool support head 80.

As seen in FIGURE 2, the pattern 116 is positioned substantially directly below the tool support head 86 thereby placing it in an out-of-the-way position. By virtue of this fact, the operator of the lathe will be able to approach the bed 18 as closely as he wishes and in fact substantially as close as he would stand if the lathe were operated without using the duplicator of the present invention. As a result, the operator can observe the formation of cuts just as closely as when the lathe is operated in the usual way. Moreover, the follower 100 can be watched throughout operation as its position changes with respect to the pattern. This is a distinct advantage since the movement of the cutting head can be anticipated more reliably.

It should be understood that the ball bushings upon which the shafts 38, 40, '72 and 74 are mounted will cause very little friction thus eliminating the need to exert heavy pressure upon the wood turning or duplicating follower 100 or on the work itself which, if required, could cause a safety hazard or danger to the operator or an observer. Moreover, since the bearing blocks 50 through 53 are able to pivot with respect to the slide means they are self-positioning with respect thereto and for that reason will have no tendency to bind. In addition, since the bearing blocks 50 through 53 are identical in construction, substantial production economies can be realized.

When the invention is placed in use, the operators hands are positioned upon the handles 92 and 94 and in this location are in a relatively safe area as compared to the position required in some prior art devices or in relation to the position in which the hands are placed in conventional wood turning lathes. Furthermore, the cutting tool of the invention is fastened securely in place and thus eliminating the possibility that it might slip out of the operators hands and strike either an operator or observer. The present invention thus functions as a safety device as well as a means to facilitate the teaching of modern lathe techniques.

The invention is capable of performing numerous, functions both safely and accurately. For example, the

invention can be used in making matched sets of legs either straight, tapered or irregular in cross-sectional configuration. It can also be used for the production of bowls, dishes, cylinders or tapered cones. It can be used for the production of face-off pieces mounted on a face plate or it can be used to cut square shoulders. It can also be used to make exact copies of original parts which may be needed as a replacement or can be used without the pattern to do free design turning.

A number of full scale models'of the present invention have been made and placed in use. The invention was found to be relatively low in cost, rugged in construction and reliable in operation. Moreover, while it was found to have general utility, it was particularly useful as a teaching instrument in aiding the instruction of students. In this application it provides increased safety, ease of operation and enables a student to produce superior results compared with what he would be able to produce Without the invention thereby increasing the students interest.

It is apparent that many modifications and variations of this invention as her inbefore set forth may be made without departing from the spirit and scope thereof. The specific embodiments described are given by way of example only and the invention is limited only by the terms of the appended claims.

I claim: I

1. A duplicator attachment for a lathe, said attachment comprising in combination, first and second support brackets, said brackets being adapted to be secured to the ends of a bed of said lathe, a pair of upwardly extending support members upon each of said brackets, a first pair of parallel cylindrical slide rods rigidly secured between aligned pairs of said upwardly extending support members and positioned longitudinally of the bed of said lathe, a pair of longitudinally spaced bearing blocks slidably mounted upon each of said rods, each of said bearing blocks being separate from each other including a first bore extending longitudinally therethrough at its upper end, said slide rods extending through said first bores, a second bore positioned below and extending transversely of said first pair of rods, a second pair of parallel and longitudinally spaced apart slide rods extending transversely of said first pair and projecting through said second bores of each of said pairs of bearing blocks, a tool support head secured at its lower end to a pair of adjacent ends of said second pair of slide rods and extending upwardly therefrom, a tool bit at the upward end of said tool support head, at least one handle means rigidly afiixed to said tool support head, an elongated guide member rigidly secured to said tool support head and extending downwardly therefrom, first and second longitudinally spaced pattern support members aifixed to said lathe bed at longitudinally spaced positions and adapted to receive therebetween a pattern positioned substantially immediately below said tool support head.

2. A duplicator adapted to be used on a lathe having a lathe bed with a front and rear side, said duplicator comprising in combination a pair of bracket members secured to the lathe bed, a pair of support portions on each bracket member, a first elongated member secured between the support portions on the front side of the lathe bed, the second elongated member secured to the support portions on the rear side of the lathe bed, a slid-e support assembly connected to said elongated members, said slide support assembly being mounted for longitudinal movement upon the elongated members, said slide support assembly comprising four spaced apart blocks, two such blocks supported upon each elongated member, a pair of horizontally disposed and transversely extending slide rods mounted upon the support head and extending through the blocks, said cutting tool support head being mounted upon the front side of the bed and supported by the slide support assembly for rectilinear movement above said lathe bed along the axis extending between the front and rear sides, a tool bit on the support head, a cutting tool mounted upon the tool bit and a fastener for securing the cutting tool in position on the support head, at least one gripping means on the cutting tool support head, said gripping means being mounted upon the support head on the side thereof adjacent the front side of the lathe whereby the gripping means can be grasped by an operator positioned at a station on the front side of the lathe and a pattern follower mounted upon the support head and including a pattern engaging portion positioned below the support head at an elevation spaced below the level of the elongated member upon which the support head is mounted.

3. A duplicator adapted to be used on a lathe having a lathe bed with a front and rear side, said duplicator comprising in combination, a pair of bracket members secured to the lathe bed, a pair of support portions on each bracket member, a first elongated member secured between the support portions on the front side of the lathe bed, the second elongated member secured to the support portions on the rear side of the lathe bed, a slide support assembly connected to the elongated members, said slide support assembly being mounted for longitudinal movement upon the elongated members, a cutting tool support head mounted upon the front side of the lathe bed and supported 'by the slide support assembly for rectilinear movement above the lathe bed along an axis extending between the front and rear sides, a tool bit on the support head, a cutting tool mounted on the tool bit and a fastener for securing the cutting tool in position on the support head, at least one gripping means on the cutting tool support head, said gripping means being mounted upon the support head on the side thereof adjacent the front side of the lathe whereby the gripping means can be grasped by an operator positioned at a station on the front side of the lathe and a pattern follower mounted on the support head and including a pattern engaging portion positioned at an elevation below the level of the elongated member upon which the support head is mounted, a pair of horizontally disposed transversely extending parallel slide rods mounted rigidly upon the rearward side of the support head and positioned vertically of the elongated members, a first set of bearings comprising at least two laterally spaced apart longitudinally extending and parallel bearing members, one mounted on each of the elongated members, the second set of bearing members comprising at least two longitudinally spaced laterally extending parallel bearing elements, one of the second set of bearings being mounted upon each of the slide rods, the bearing of the second set being disposed vertically of the first set and adjacent thereto and each bearing of the first set being rigidly secured to the adjacent bearing of the second set.

4. A duplicator adapted to be used on a lathe having a lathe bed with a front and rear side, said duplicator comprising in combination, a pair of bracket members secured to the lathe bed, a pair of support portions on each bracket member, a first elongated member secured between the support portions on the front side of the lathe bed, the second elongated member secured to the support portions on the rear side of the lathe bed, a slide support assembly connected to the elongated members, said slide support assembly being mounted for longitudinal movement upon the elongated members, a cutting tool support head mounted upon the front side of the lathe bed and supported by the slide support assembly for rectilinear movement above the lathe bed along an axis extending between the front and rear sides, a tool bit on the support head, a cutting tool mounted on the tool bit and a fastener for securing the cutting tool in position on the support head, at least one gripping means on the cutting tool support head, said gripping means being mounted upon the support head on the side thereof adjacent the front side of the lathe whereby the gripping means can be grasped by an operator positioned at a station on the front side of the lathe and a pattern follower mounted on the support head and including a pattern engaging portion positioned at an elevation below the level of the elongated member upon which the support head is mounted, slide rods mounted upon the rearward side of the support head and extending toward the rear of the lathe from the support head in a horizontal plane, at least three pairs of bearings, each pair comprising an upper and a lower rigidly connected bearing positioned at right angles to each other with one such bearing mounted over the elongated member and the other such bearing mounted over one of said slide rods.

References Cited by the Examiner UNITED STATES PATENTS Newman 82-14 Shawver 142-38 Tautz 14238 Burton 14238 Schutz 1436.1

Paine 8236 Mitchell 143-474 ROBERT C. RIORDON, Primary Examiner.

WILLIAM W. DYER JR., LESTER M. SWINGLE,

Examiners. 

1. A DUPLICATOR ATTACHMENT FOR A LATHE, SAID ATTACHMENT COMPRISING IN COMBINATION, FIRST AND SECOND SUPPORT BRACKETS, SAID BRACKETS BEING ADAPTED TO BE SECURED TO THE ENDS OF A BED OF SAID LATHE, A PAIR OF UPWARDLY EXTENDING SUPPORT MEMBERS UPON EACH OF SAID BRACKETS, A FIRST PAIR OF PARALLEL CYLINDRICAL SLIDE RODS RIGIDLY SECURED BETWEEN ALIGNED PAIRS OF SAID UPWARDLY EXTENDING SUPPORT MEMBERS AND POSITIONED LONGITUDINALLY OF THE BED OF SAID LATHE, A PAIR OF LONGITUDINALLY SPACED BEARING BLOCKS SLIDABLY MOUNTED UPON EACH OF SAID RODS, EACH OF SAID BEARING BLOCKS BEING SEPARATE FROM EACH OTHER INCLUDING A FIRST BORE EXTENDING LONGITUDINALLY THERETHROUGH AT ITS UPPER END, SAID SLIDE RODS EXTENDING THRUGH SAID FIRST BORES, A SECOND BORE POSITIONED BELOW AND EXTENDING TRANSVERSELY OF SAID FIRST PAIR OF RODS, A SECOND PAIR OF PARALLEL AND LONGITUDINALLY SPACED APART SLIDE RODS EXTENDING TRANSVERSELY OF SAID FIRST PAIR AND PROJECTING THROUGH SAID SECOND BORES OF EACH OF SAID PAIRS OF BEARING BLOCKS, A TOOL SUPPORT HEAD SECURED AT ITS LOWER END TO A PAIR OF ADJACENT ENDS OF SAID SECOND PAIR OF SLIDE RODS AND EXTENDING UPWARDLY THEREFROM, A TOOL BIT AT THE UPWARD END OF SAID TOOL SUPPORT HEAD, AT LEAST ONE HANDLE MEANS RIGIDLY AFFIXED TO SAID TOOL SUPPORT HEAD, AN ELONGATED GUIDE MEMBER RIGIDLY SECURED TO SAID TOOL SUPPORT HEAD AND EXTENDING DOWNWARDLY THEREFROM, FIRST AND SECOND LONGITUDINALLY SPACED PATTERN SUPPORT MEMBERS AFFIXED TO SAID LATHE BED AT LONGITUDINALLY SPACED POSITIONS AND ADAPTED TO RECEIVE THEREBETWEEN A PATTERN POSITIONED SUBSTANTIALLY IMMEDIATELY BELOW SAID TOOL SUPPORT HEAD. 